What is a carbon footprint?
When we burn fuel (petrol, diesel, coal, gas) to move or to make electricity, we release carbon dioxide (CO2). Too much CO2 traps heat in the air and warms the Earth.
Your carbon footprint is the amount of CO2 your daily life causes. The main parts are:
- Travel: cars and motorbikes release much more CO2 per person than buses, trains, cycles or walking.
- Power: most electricity still comes from burning fuel, so wasted electricity is wasted carbon.
- Food and waste: making, carrying and throwing away things uses energy and releases gases.
Investigating carbon habits (survey)
Make a simple survey for your class or family.
- Choose three questions: How do you get to school? How many hours are lights and fans left on in empty rooms? How many plastic bags do you use a week?
- Ask 10 people and tally the answers.
- Make a bar chart with each answer as a bar.
- Find the biggest habit: the tallest bar is where a change helps most.
Use only the numbers people give you. Do not name anyone on the chart.
Proposals: simple low-carbon changes
A good proposal is small, clear and easy to start. Use the pattern Habit → Change → Benefit → Who.
- Travel: walk, cycle or take a bus for trips under 2 km; share a ride if you must use a car.
- Power: switch off lights and fans when leaving; use LED bulbs; open curtains by day.
- Waste: carry a cloth bag and a bottle; repair before replacing; compost kitchen waste.
- Food: eat local and seasonal food; take only what you can finish.
Add a number: If 30 students walk instead of coming by car one day a week, 30 trips of fuel are saved every week.
Publicity materials: poster, slogan, short talk
To make others act, your message must be short and clear.
- Poster: one big picture, one short slogan, one action. Keep words to about 15.
- Slogan: short, easy to say, and has a rhythm: "Switch off, save more." "Walk a mile, wear a smile."
- Short talk (1-2 minutes): a hook, your survey result, your proposal, one action.
- Facts: use only numbers you checked, and say where they came from.
Try it: for one week, tick every day you switch off the light when leaving, then show the tick chart in your poster.
Key formulas and definitions
- Carbon footprint = CO2 from travel + power + food + waste
- Saved = usual cubes - green cubes (3D: 14 - 3 = 11 per day)
- Week saved = day saved x 7
- Proposal = habit → change → benefit → who
Worked examples
1. In the 3D, Travel drops from 6 cubes to 1. How many cubes are saved?
6 - 1 = 5 cubes saved.
2. Power saves 3 cubes a day. How many in a week?
3 x 7 = 21 cubes in a week.
3. Write a proposal for school lunch waste.
Habit: half of lunch is thrown away. Change: take smaller servings and add more if needed; compost peels. Benefit: less waste and less carbon. Who: every student, with the canteen.
4. Make a 6-word slogan for saving electricity.
Switch off. Save light. Save Earth.
Common mistakes
- Thinking a carbon footprint is only about cars: power, food and waste count too.
- Making huge promises: small habits that you really keep are better.
- Using numbers in posters that you did not check.
- Writing a poster with too many words, so nobody reads it.